A couple of things to remember about You Tube:
1) When you sign up, choose whether or not you want your web history enabled or not. There are advantages and disadvantages to both.
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2) You can save videos you like in playlists by clicking on the "add to" button.
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3) You can subscribe to users you like. For example if you really like Bill Nye the Science Guy you can subscribe to his videos so you have instant access any time you like.
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4) You can get to the videos you have saved and subscribed to by clicking on your login in the top right hand corner!
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